Stapler



FIG. 1 is a top, front and side perspective view of a stapler, showing my new design;

FIG. 2 is a side elevational view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 top plan view thereof; and,

FIG. 6 is a bottom plan view thereof. 

The ornamental design for a stapler, as shown and described. 